Cushion body structure for noise prevention

ABSTRACT

A cushion body structure (1) is connected to a planar fastening body (4) with a cushion material (6), by spacing in a proper distance at least a part along a side end (7) of the planar fastener (4) from the cushion material (2, 3) positioned in proximity of it through a space (11). When a skin material (12) fastened to the planar fastener (4) is tensioned, it is not moved to separate from and fasten to the skin material again and thereby does not produce noise.

TECHNICAL FIELD

The present invention relates to a cushion body structure for a car seatand, in particular, relates to a cushion body structure available forpreventing noise produced by a repetition of separating and fasteningbetween a skin and a planar fastening material by the manner ofattaching the skin material to a cushion material through the planarfastening material.

BACKGROUND OF THE ART

Several methods for attaching a cushion material which is made of afoamed body forming a body portion of a car seat and a skin materialattached on its surface have been known and publicly used. Specificallyas a method of attaching a skin material to a cushion material with aconcave surface, a back surface of the skin was bonded over a surface ofthe cushion material or an integral molding method of injecting urethaneinto a cushion material molding die after setting a skin material haveoften been used. However, in either method, their own production systemsfor carrying out such methods are required and it is difficult toinstall such systems in a continuous assembly line, thereby increasingthe cost for transferring and manipulating materials. Also, such amethod in the art is a mass production system and it is thus required tomaintain its operation rate. However it is difficult to control a volumecorresponding to a variation of the production rate. Thus, such aproduction method results in low productivity and causes a rise in cost.

It is intended to use a planar fastening material in order to facilitateattaching a skin material to a cushion material to eliminate the aboveproblems. The planar fastening material is so called a planar fastenerand has innumerable hooked or ring-shaped small protrusions imbedded ona knitted or textile base sheet. The hooked or ring-shaped smallprotrusions fasten and mechanically attach to a back side of the skinmaterial. However, in this mechanical attachment of the skin by theplanar fastening material, unexpected troubles are found in practice.

Explaining the troubles with reference to FIG. 4, when a person gets offa seat 15, a tensile force as indicated by an arrow F1 acts on a skin16. Since the skin 16 is attached on the planar fastening material 17 bythe mechanical tensile force, the skin is instantaneously separated fromthe planar fastening material, when a component F2 of the tensile forceF1 exceeds the mechanical attachment force. However, if the force F1 isreduced by movement of the person, then the skin is immediately fastenedto the planar fastening material to revert to its initial state again.Such a repetition of separating and fastening produces noise orvibration, and users may have distrust of the quality of the seat andthey may also feel displeasure and wariness. Also, they may mistake thenoise for static electricity.

OBJECTS

Therefore, it is an object of the present invention to provide a cushionbody structure for a car seat which prevents a repetition of separatingand fastening between a planar fastening material and a skin materialand prevents the resultant production of noise or vibration in a seat inwhich the skin material is attached to the cushion material by theplanar fastening material.

DISCLOSURE OF THE INVENTION

In a cushion body structure of a car seat constructed by molding aplanar fastening body for fastening a skin material to a cushionmaterial, the present invention provides a cushion body structure whichhas a proper distance of open space without joining at least a part ofthe end portions along the planar fastening body to the cushion materialpositioned in proximity to it, so that the planar material follows theskin material and is not separated by an external force such as atensile force or the like which acts on the surface material whengetting on and off the car seat.

Specifically, the planar fastening material is fixed into the cushionmaterial in a form of the planar fastening body integrated with asupport material such as slab urethane foam. Thickness of the slaburethane is not specified in a certain range but it may be 5 to 15 mm,preferably 10 mm. While such a planar fastening body is attached topreferably the whole of a seating surface of a cushion material or atleast a main part of the cushion material, in the present invention aside end and preferably a lower back side of the planar fastening bodyis spaced a proper distance from sides and a center of the cushionmaterial. The proper distance is found to be about 5 mm to about 20 mm.Therefore, if the cushion body structure of the present invention is cutaway over an area including the planar fastening body, a linear shapedspacing or an L-shaped spacing from the side end to the lower side isformed between the side end of the planar fastening body and the cushionmaterial. Thus, the side end of the planar fastening body can follow anexternal force to extend or freely move, and even though the skinattached on its upper surface is tensioned by a tension force F1 (FIG.4) it is facilitated to behave by following it and a force component F2is not produced, and thereby noise or vibration produced in the art bymoving a user's body is not produced because a separation between theskin material and the planar fastening material is not generated andthey are not attached again.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a lateral cross-sectional view showing a section of a cushionstructure available for preventing noise in accordance with the presentinvention.

FIG. 2 is a lateral cross-sectional view of a molding die for foaming acushion body shown in FIG. 1.

FIG. 3 is an enlarged fragmentary sectional view of a main part of thecushion body structure shown in FIG. 1.

FIG. 4 is a schematic illustration describing how an objectionable noiseis produced in a cushion body employing a planar fastener body of theprior art.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention is described referring to thedrawings. FIG. 1 is a view of a cross section cut in a lateral directionof a cushion body of a car seat providing the noise preventing structureof the present invention. The cushion body 1 consists of a cushionmaterial such as foamed urethane and a planar fastening body 4 coupledto it. The cushion body 1 consists of a main portion 2 forming a seatand side portions 3, 3 rising on its right and left hand sides. Theplanar fastening body 4 is preferably connected on the body portion 2 byintegrally molding. The planar fastening body 4 consists of a structureof laminated and molded planar fastening material 5 and a foamed body,as its support material, which is basically of the same characteristicsas the cushion material, and preferably a slab of urethane layer 6. Anopen space 11 as a main feature of the present invention is formedbetween the planar fastening body 4 and the proximate side portions 3,3, as shown in FIG. 1.

Referring to enlarged FIG. 3, a side end 7 of the planar fasteningmaterial 5 and a side end 8 of the slab urethane layer 6 are both spacedfrom the side 3, to form the open space 11. Moreover, the space 11 iscontinuously stepped into a lower surface 9 of the slab urethane layer 6in a reversed L-shape as shown in FIG. 3, so that a lower side end 10 ofthe slab urethane layer 6 is spaced from the cushion material 2, 3 tofreely move. The main part of lower surface 9 of the slab urethane layer6 is generally connected with body portion 2 of the cushion material.

The planar fastening material 5 of the planar fastening body 4 has alarge number of small protrusions (not shown ) provided on the surface,and a skin material 12 as shown by a dotted line is pressed and fixedthereon to be mechanically connected to fastener body 4. It should benoted that the skin material 12 is shown only on the left hand side inFIG. 1 but the skin material similarly covers and is fixed on the righthand side. If an external force F1 described above referring to FIG. 4acts on the skin material 12, then the skin material 12 rises togetherwith the side end 7 of the planar fastening material 5, and a proximatepart of the free side end 8 of the slab urethane layer 6 is naturallyraised thereby. As a result, a separation of the skin material 12 isavoided by interlocking the skin material 12 and the planar fasteningbody 4, and it also avoids fastening again when the tension F1 isreleased, thereby not producing noise or vibration.

A cushion body 1 of the present invention is produced by a molding dieas shown in FIG. 2. A lower die 20 of the molding die has a desiredthree-dimensional curved bottom surface 21 in its central part. In bothsides of the bottom surface 21 of the molding die, partitions 22 forforming the open space 11 are provided extending upwardly with hookedportions 23 curved inwardly at their tips. The planar fastening body 4is installed and clamped under the hooked portions 23 in a state asshown by the dotted lines of FIG. 2. Then, pouring an undiluted solutionfor the cushion materials downwardly into the lower molding die 20 inaccordance with the usual manner and foaming takes place after sealingwith an upper die 24. The planar fastening body 4 is pressurized to thebottom surface 21 of the die 20 as shown by the shaded line by theinternal pressure of molding and is generally connected with the bodyportion 2. However, by presence of the partitions 22, 22 and the hookedportions 23, 23, the side ends 7, 8 of the planar fastening body 4 areseparated from the cushion body side portions 3, 3 and its lower side 10is also separated from the side and the body portions so that the sideends 7, 8 being capable of freely moving are formed therein to performan effective action for preventing noise.

As an embodiment in detail, in order to form a seat profile having athree-dimensional curved surface as shown in FIG. 1, the planarfastening body 4 consists of the planar fastening material 5 (a planarfastener of sold by a company known as KURARE) and slab urethane foam 6as a support material with a thickness of 5 to 15 mm and a density of0.018 g/cm³ to 0.040 g/cm³ which is selected by thickness and densityavailable to correspond to a feeling of the seat and the degree of adesired curved surface profile. In practice, the planar fastening body4, which is laminated-molded of a support material 6 of urethane foamhaving a thickness of 10 mm and a density of 0.034 g/cm³ and the planarfastening material 5, is employed to form a seat profile having a depthof the curved surface of 10 mm. It is found that a good distance forspacing the cushion material 2, 3 from the planar fastening body is inthe range of 5 to 20 mm, according to the size of the bucket seat. Inpractice, with respect to a bucket seat shape with a size of 85 mm, bysetting the outer side spacing distance at 5 mm, it is found possible toembody a high quality seat that does not produce noise and to maintain aseat shape having a good feeling for seating.

AVAILABILITY OF THE INVENTION

As described above, according to the present invention, it isconstructed with such effectiveness that noise or vibration is notproduced on a planar fastening body 4 by spacing a side end 7, 8 of theplanar fastening body 4 connected with a cushion material 6 of a carseat from a cushion material 3 at a predetermined distance. This permitsa behavior such as extending or freely moving or the like of the planarfastening material 5 by following a skin material 12 when acted upon byan external force such as a tension force or the like by moving a user'sbody across the skin material which is mechanically attached to theplanar fastening body 4 so that the attachment force is not broken.Thus, it is constructed with such effectiveness as to be easy to adapt aplanar fastening body 4, which is considerably more economic andefficient attaching manner comparing with the manner of attaching a skinto a car seat in the prior art, so as to facilitate a reduced cost andto permit adjusting volume of production.

We claim:
 1. A cushion structure for a vehicle seat comprising, acushion body having a main portion and upwardly extending side portions,a fastening body having a support layer of cushioning materialintegrally formed with said main portion of said cushion body anddisposed between said side portions, said fastening body having a planarfastening material carrying fasteners disposed on the surface thereofand being laminated to said support layer, a surface material positionedover said side portions of said cushion body and said fastening body andmechanically attached to said fastening body, an open space providedbetween said fastening body and said side portions of said cushion bodyby spacing the side ends of said fastening material and said supportlayers from said cushion body, thereby precluding separation of saidsurface material from said fastening body upon the application ofexternal forces to said surface material, and lower side ends of saidsupport layer spaced from said main portion of said cushion body to forma continuation of said open space in the form of a reversed L-shape,thereby permitting free movement of said side ends of said supportlayer.
 2. A cushion structure according to claim 1 wherein said sideends are spaced from said side portions of said cushion body in a rangeof 5 to 20 mm.
 3. A cushion structure according to claim 1 wherein saidplanar fastening material has a plurality of protrusions formechanically engaging said surface material.